docs: def album_to_ref(album):
      """Convert a mopidy album to a mopidy ref."""
      name = ''
      for artist in album.artists:
          if len(name) > 0:
              name += ', '
          name += artist.name
      if (len(name)) > 0:
          name += ' - '
      if album.name:
          name += album.name
      else:
          name += 'Unknown Album'
      return Ref.directory(uri=album.uri, name=name)